The necessity and utility of devices for conveying and uniformly dispensing materials for processing or packaging is widely recognized and numerous devices exist or have been proposed to accomplish these tasks. One class of devices employs rotating tubes or impellers, and combinations thereof, to distribute free flowing materials. Although these devices are capable of accomplishing the specific tasks for which they are designed, they suffer from several disadvantages which the present invention is designed to overcome.
The present invention relates to a device for delivering, dispensing and distributing free-flowing materials, by gravity and centrifugal force, within a closed container such as a silo or a railroad car. More particularly, the apparatus described herein is adapted to convey and uniformly distribute a wide variety of granular or pulverized materials, at a controlled rate, by means of a delivery system of simplified, integral design, which is insertable in a variety of physical locations. The distribution of the materials is accomplished by a unique "spin filling" mechanism. This apparatus for accomplishing this task is comprised of a elongated, hollow delivery tube mounted within a housing for rotation about its vertical axis. The delivery tube has a port for receiving materials from above and apertures in its walls at its base, thereby permitting the movement of free-flowing materials through the tube and to the container. Additionally, the delivery tube and housing include two significant features which contribute to its uniqueness: first, the drive means for rotating the delivery tube is located to the exterior of the tube and is integral therewith; hence, the flow path is unencumbered by any drive shafts and permits an enlarged cross section with no internal obstructions. Second, integral with the base and adjacent to apertures in the walls of said delivery tube, there is a horizontal receiving platform having vertically-oriented impeller blades, spaced with respect to the axis of rotation, for deflecting the material from its downward path and out through said apertures. Impeller blades, per se, are not new, but since the platform and impeller blades thereon are integral with the tube and adjacent to said apertures, no additional internal drive means is necessary for rotating the platform and impellers along with the delivery tube about a central vertical axis. In a variation of the design; a second closure tube, internal of the rotating conveying tube, can be raised and lowered to vary the size of the apertures at the base of the rotating tube.
The combination of these features simplifies the design of the system and makes it less cumbersome. It also reduces the likelihood of clogging or breakdown, and facilitates the movement and insertion of the distributing tube or cylinder to and into a wide variety of relatively enclosed spaces.